An aircraft comprises several external aerodynamic parts such as the radome and other external cowlings which are mounted so as to move relative to the fixed structure formed by the fuselage.
Because of their external position, these parts sustain considerable mechanical forces including the aerodynamic forces that are applied in flight to the fuselage of the aircraft.
Consequently, these moveable external parts must be solidly and firmly connected to the fixed structure of the aircraft, notably when the latter is in use.
Accordingly, standard fastening elements such as screws are used, their number and their distribution being adapted to ensure a rigid connection.
In order to ensure the durability of the assembly during the operation of the aircraft, the fastening screws must be locked by means preventing their unscrewing.
However, according to an assembly constraint, and always because of the external position of these moveable parts, the fastening screws are accessible only from the outside of the aircraft and only at one of their ends: only the screw head or the nut mounted on the screw can be reached.
Also, conventional locking means of the lock nut type cannot be used because these means wear in the long term.
The use of tab washers is no more suitable because the tabs may present risks of breakage after a certain number of removals and reinstallations.
Finally, the use of safety wire cannot be envisaged because of the number of screws and the considerable time needed to take the necessary precautions when removing and reinstalling the safety wire.
According to other assembly constraints, the fastening elements must be reusable, and, as much as possible, fulfill their function throughout the service life of the aircraft.
And, according to recent assembly constraints, these fastening elements are situated in a lightning hazard attachment zone and they must allow the production of a compact assembly.
Also, the present invention aims to respond to the aforementioned assembly constraints and to alleviate the drawbacks of the prior art.